Influence of CdS thin films growth related with the substrate properties and conditions used on CBD technique

摘要

CdS polycrystalline thin films have been used as window layer in solar cells; the quality of the CdS-partner plays an important role in the photovoltaic device performance. CdS thin films were deposited using Chemical Bath Deposition (CBD) and photoassisted-CBD technique. The SnO_2:F substrates used in this work were treated with HCl (0.1M) and some of them were annealed in different atmospheres (Ar and O_2). The properties of CdS thin films were influenced by the HCl treatment, position and the movement of substrates inside the reactor glass. CdS samples were deposited in areas of 4 cm~2, 50 cm~2 and 100 cm~2; obtaining thin films with thickness of 35 - 300 nm with good crystalline quality and uniform morphology. All samples presented optical transmittance around of 85 - 91% and average gap energy of 2.5 eV.